Valve system for introducing objects into anatomical body portions

ABSTRACT

A valve assembly adapted for introduction of an elongated object into a patient&#39;s body having a first valve formed of a resilient material and defining an aperture for reception of the object, the aperture being configured and dimensioned such that insertion of the object into the aperture will cause the resilient material defining the aperture to resiliently engage the outer surface of the object in a fluid tight manner. A second valve is positioned adjacent and distal of the first valve in general alignment therewith, whereby the second valve defines an aperture in general alignment with the aperture of the first valve, and is formed of a flexible material at least in the region defining the aperture. A pair of manually operable clamps are provided to selectively permit the aperture of the second valve to be opened or closed so as to permit entry of the object such that the object first passes through the first valve and then the second valve prior to entry into the patient&#39;s body.

This is a continuation of U.S. application Ser. No. 07/992,143 filedDec. 17, 1992, now U.S. Pat. No. 5,304,163, which is a continuation ofU.S. application Ser. No. 07/711,756, filed Jun. 7, 1991, now U.S. Pat.No. 5,180,373.

BACKGROUND OF THE INVENTION

1. Field Of The Invention

This invention relates to valve systems of the type adapted to allow theintroduction of a surgical instrument into a patient's body. Inparticular, the invention is applicable to a cannula assembly and thelike wherein a cannula extends from a valve assembly and is intended forinsertion into a patient's body and an instrument is inserted into thepatient's body through the cannula.

2. Background Of The Prior Art

In laparoscopic procedures surgery is performed in the interior of theabdomen through a small incision; in endoscopic procedures surgery isperformed in any hollow viscus of the body through narrow endoscopictubes or cannula inserted through a small entrance incision in the skin.Laparoscopic and endoscopic procedures generally require that anyinstrumentation inserted into the body be sealed, i.e. provisions mustbe made to ensure that gases do not enter or exit the body through thelaparoscopic or endoscopic incision as, for example, in surgicalprocedures in which the surgical region is insufflated. Moreover,laparoscopic and endoscopic procedures often require the surgeon to acton organs, tissues, and vessels far removed from the incision, therebyrequiring that any instruments used in such procedures be relativelylong and narrow.

For such procedures, the introduction of a tube into certain anatomicalcavities such as the abdominal cavity is usually accomplished by use ofa system comprised of a cannula assembly and a trocar. A cannulaassembly is formed of a cannula attached to a valve assembly which isadapted to maintain a seal across the opening of the valve assembly.Since the cannula is in direct communication with the internal portionof the valve assembly, insertion of the cannula into an opening in thepatient's body so as to reach the inner abdominal cavity should beadapted to maintain a fluid tight interface between the abdominal cavityand the outside atmosphere.

Since surgical procedures in the abdominal cavity of the body requireinsufflating gases to raise the cavity wall away from vital organs, theprocedure is usually initiated by use of a Verres needle through which agas is introduced into the body cavity. Thereafter, a trocar, which is asharp pointed instrument, is inserted into a cannula assembly and usedto puncture the peritoneum, i.e. the inner lining of the abdominalcavity wall. The gas provides a slight pressure which raises the wallsurface of the peritoneum away from the vital organs thereby avoidingunnecessary contact with the organs by the instruments inserted into thecannula. This procedure also provides the surgeon with an adequateregion in which to operate. Laparoscopic or endoscopic surgicalinstruments may then be inserted through the cannula to perform surgerywithin the abdominal cavity or other body portion. The cannula is alsoutilized for introducing tubes into the body as for drainage purposes orthe like.

In view of the need to maintain the atmospheric integrity of the innerarea of the cavity, a valve assembly which permits introduction of atrocar or any surgical instrument and which permits selectivecommunication of the inner atmosphere of the cavity with the outsideatmosphere is desirable. In this regard, there have been a number ofattempts in the prior art to provide such atmospheric integrity.

One form of cannula assembly includes a valve assembly which includes aflapper valve which is pivotally mounted within the valve assembly andis automatically opened by the trocar or other object when it isinserted into the proximal end of the valve assembly. See, e.g., U.S.Pat. No. 4,943,280 to Lander.

U.S. Pat. No. 4,960,412 relates to a catheter introducing system whichincludes a valve assembly having dual flexible resilient gaskets whichpermit introduction of a catheter by providing dual openings which aredimensioned to contact a catheter tube introduced into the unit.Introduction of the tube is accomplished by introducing the tube intothe openings of the gaskets. A first valve prevents or minimizes theflow of blood from the valve assembly unit when the catheter tube isabsent and the second valve prevents or minimizes the flow of blood fromthe valve assembly when the catheter tube is present.

Another valve includes finger operated levers for controlling an innervalve formed of a plurality of radially movable members which join inadjacent relation to close the valve opening and which separate topermit entry of an element into the valve opening. The members areconcentrically positioned and arranged to block the opening when thelevers are at rest and to open in a manner to form a substantiallycircular passage-way when the levers are squeezed toward each otheragainst the bias of a spring positioned therebetween.

Although attempts have been somewhat successful in providing a valveassembly which maintains the integrity of the atmospheric interfacebetween the inlet of the valve assembly and the atmosphere outside thevalve assembly, none have provided the degree of control to the userwhereby opening adapted to facilitate the introduction of an instrumentinto the human body can be controlled selectively, opened or closed, insequence and in a manner which positively retains the desired interfacebetween the two atmospheres as may be required by the operator. Thepresent invention provides a valve assembly which may be incorporatedinto a cannula assembly or utilized in combination with any type oftubular member for introduction into the body of a patient whilepermitting introduction of instruments into the body. At all times, thesurgeon maintains control over the interface between the atmosphereswithin and without the patient's body. Moreover, the present inventionmakes it possible to introduce instruments of varying sizes into thebody and insures the maintenance of a gas seal despite instrumentmanipulation therethrough.

SUMMARY OF THE INVENTION

A valve assembly adapted for introduction of an elongated object into apatient's body is provided which comprises first valve means formed of aresilient material and defining an aperture for reception of the object,the aperture being configured and dimensioned such that insertion of theobject into the aperture will cause the resilient material defining theaperture to resiliently engage the outer surface of the object in asubstantially fluid tight manner. Second valve means is positionedadjacent the first valve means in general alignment therewith, thesecond valve means defining an aperture in general alignment with theaperture of the first valve means and being formed of a flexiblematerial at least in the region defining the aperture. Means is providedto selectively permit the aperture of the second valve means to beopened or closed so as to permit entry of the object.

Preferably, the valve assembly comprises valve body means which definesproximal inlet and distal outlet openings. The first valve means isformed of an elastomeric resilient material and extends across theproximal inlet opening of the valve body, and defines an apertureconfigured and dimensioned for reception of the object in a manner suchthat resilient material surrounding the aperture engages the surface ofthe object to provide a substantially fluid tight seal which preventspassage of fluids past the interface. The second valve means ispositioned adjacent and distally of the first valve means and both valvemeans extend across the proximal inlet opening of the valve body. Thesecond valve means includes an aperture defined at least in part byflexible elastomeric material in general alignment with the aperture ofthe first valve means and of dimension sufficient to permit passage ofthe object after the object is passed through the first valve means.Means is provided to bias the flexible material defining the aperture ofthe second valve means to a configuration whereby the aperture is closedto form a fluid tight seal prior to inserting the object therethrough,and means is provided to open the aperture of the second valve means topermit passage of the object therethrough after the object is passedthrough the first valve means. Preferably, means to open the aperture ofthe second valve means is manually operable.

The objects contemplated are surgical instruments such as clip appliers,dissectors, graspers, laser and electrocautery devices, drainage orfluid introduction tubes or the like. The first valve means ispositioned across the proximal opening of the valve body and the secondvalve means is positioned adjacent the first valve means and distallythereof. Further, the first and second valve means are preferably formedintegrally of a flexible elastomeric resilient material, with the firstvalve means connected to the second valve means at the proximal endsthereof, the first valve means being positioned at least partiallywithin the second valve means. The first and second valve means arejoined at their proximal ends and are attached to the valve body acrossthe proximal opening. The valve body includes a neck which extendsdistally of the distal end thereof, the neck defining an openingcommunicating with the interior of the valve body means. Further, thedistally extending neck of the valve body is adapted to receive atubular cannula such that the cannula extends distally of the valvebody.

The second valve means comprises an elastomeric generally cylindricallyshaped member which is preferably connected integrally at the proximalend thereof to the proximal end of the first valve means and is open atthe distal end. The distal opening of the second valve means is capableof being closed by collapsing the distal end until the half portionsthereof resiliently contact each other to form a substantial fluid tightseal. The distal end of the second valve means is biased toward theclosed fluid tight position by a clamp which is positioned and adaptedto bias the open end of the second valve means toward the collapsedconfiguration. The clamp comprises a pair of clamp blades, each bladeconnected to a portion of the distal open end of the second valve means.The clamp blades are each biased toward each other to close the distalopening of the second valve means by a respective torsion spring mountedwithin the valve body. Each clamp blade is connected to a pivotal armand each pivotal arm is biased toward the position corresponding to theclosed position of the second valve means. The pivotal arms are mountedfor pivotal movement toward the valve-open position by reception into anaperture of at least one slidable pin. The pins are movable manually byengagement by the user's fingers.

The first and second valve means are preferably attached to andsupported by an annular ring which includes a plurality of elongatedfingers which extend distally therefrom and are positioned within thefirst valve means in contact with the inner surface thereof. The fingersprovide an interface between the first valve means and objects insertedtherein and assist in spreading the opening of the first valve means forentry of the instrument. Further, the fingers distribute the force overthe inner surface of the first valve means.

Each slidable pin has a frusto-conical shaped tip adjacent each pivotarm for engagement with the respective pivot arm when the pins are movedtoward each other by manual action of the user. Further, the valve bodyis preferably a two piece valve housing assembled at a medial interfaceand constructed of a relatively rigid plastic material such aspolycarbonate, polyethylene or the like.

In a preferred embodiment, a cannula and trocar assembly is provided forpuncturing a body wall of a patient for the introduction of elongatedobjects as surgical instruments or the like into the body of the patientwhile maintaining a substantial fluid tight seal between internal bodyportions and the outside atmosphere at all times prior to and afterinsertion of the object. The valve housing has an inlet opening at theproximal end and an outlet opening at the distal end, the distal endopening having a tubular cannula extending distally therefrom. A trocaris positioned within the valve housing and the cannula for puncturingthe body wall. Thereafter, the trocar is removed and elongated objectssuch as surgical instruments or the like may be introduced into thepatient's body through the valve assembly and cannula as describedhereinabove.

In the preferred embodiment the first and second valves are moldedintegrally of synthetic or natural rubber and are connected at a commonproximal end which defines the proximal opening. The first valve meanshas a generally conical shape and is positioned within the second valvemeans in a generally concentric fashion. The valve means are mountedonto a support ring which is used to mount the valve means to an annularportion within the valve housing.

A method is provided for selectively sealing a valve assembly forcommunication with inner portions of a patient's body while permittingintroduction of an elongated instrument therethrough, the valve assemblyhaving a proximal inlet opening and a distal outlet opening, comprisingproviding first valve means comprised of resilient material defining anopening which permits entry therethrough by the instrument whileresiliently contacting the outer surface, providing second valve meansdistal of the first valve means, and selectively controlling the openand closed condition of the second valve means to permit passage of theinstrument after entry through the first valve means.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a cannula assemblyillustrating the valve assembly constructed according to the presentinvention;

FIG. 2 is a view of the lower housing half section shown in FIG. 1 withportions of the inner valve and cannula cut away for illustrationpurposes;

FIG. 3 is a cross-sectional view of the valve assembly of the presentinvention taken along lines 3--3 of FIG. 2; and

FIG. 4 is a cross-sectional view of the valve assembly of the presentinvention, taken along lines 4--4 of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention contemplates introduction into a patient's body ofall types of surgical instruments including clip appliers, lasers,photographic devices, tubes, etc. All such objects are referred toherein as "instruments".

Referring initially to FIGS. 1 and 2, a cannula assembly 10 isillustrated having the novel valve assembly 12 constructed according tothe present invention. Valve assembly 12 includes a valve housing 15formed of upper housing half section 14 and lower housing half section16 shown separated in FIG. 1 for convenience of illustration.

The housing half sections 14,16 are formed of a suitable desirableplastic material such as polycarbonate, polyethylene or the like. Onepreferred material is LEXAN brand polycarbonate manufactured andmarketed by General Electric Company, Pittsfield, Mass. The housing halfsections 14,16 are normally attached along the seam by suitableattachment techniques such as adhesive, ultrasonic welding, or the like.

The valve housing 15 includes neck 18 at the distal end having anaperture 20 dimensioned for reception of an appropriate sheath tube suchas cannula 22 to form the cannula assembly 10. The proximal end of valvehousing 15 includes inlet opening 24 which includes annular partition 26for supporting a dual diaphragm as will be described.

Referring now to FIG. 2, the lower housing half section 16 is shown withthe upper housing half section 14 removed, so as to illustrate the novelinner valve mechanism of the present invention. The valve mechanism isshown partially cut away and in cross section. Dual flexible elastomericsealing diaphragm 30 extends across the aperture 20 of housing 15 asshown. The diaphragm 30 forms a circular rib 33 which fits tightly bysnap fit onto annular partition 26 with dual flanged circular rib 32 asshown in FIG. 2. The annular partition 26 is constructed of the samerelatively rigid plastic material such as polycarbonate, polyethylene orthe like, as the valve housing, while diaphragm 30 is constructed of anelastomeric material such as synthetic or natural rubber. Diaphragm 30is of dual walled construction as shown, with the inner wall 30a havinga central aperture 34 for reception of an instrument as will bedescribed.

Referring now to FIG. 1 in conjunction with FIGS. 3 and 4, outer wall30b has formed at the distal end, a pair of ears 36,38 which areconnected to clamp blades 40,42 as shown, by suitable pivot pins 44,46and attachment nuts 43,47. Each clamp blade 40,42 is biased in adirection toward the other by a torsion spring 48,50 having one leg inengagement with the adjacent housing wall and the other leg inengagement with pivotal arm 52,54 respectively pivotally mounted atpivot pin 56,58 as shown in FIG. 3. Each pivot arm 52,54 extends asshown, into the path of a pin 60,62 which is slidably mounted withinelongated opening 64,65 having a circular cross-section similar to thecross-section of the pins 60,62. The inner end of each pin has anopening 66,68 for reception of the appropriate pivotal arm 52,54 suchthat manually depressing the slidable pins 60,62 toward each other byengagement of transverse buttons 70,72 with the thumb and index fingercauses pivotal arms 52,54 to pivotally rotate arms 52,54 away from eachother. This motion causes clamp blades 40,42 with ears 36,38 to separatecausing outer wall 30b of dual diaphragm 30 to open at the distal end tothe configuration shown in FIG. 1. When the pins 60,62 are released, theouter wall 30b of diaphragm 30 collapses to the configuration shown inFIGS. 3 and 4 under action of clamp blades 44,46 and springs 48,50, thuscausing outer wall to collapse to the duckbill shape 74, providing afluid tight seal between the proximal end of the diaphragm 30 and thedistal end.

Referring now to FIG. 4 in conjunction with FIG. 1, inner elastomericwall 30a of diaphragm 30 defines circular central aperture 34 at thedistal end which is dimensioned less than or equal to the outer diameterof any instrument intended for entry into the proximal end of the valveassembly. Preferably, diaphragm 30 is fabricated from a material whichis sufficiently resilient to accommodate and provide a fluid seal withinstruments of varying diameters, e.g., diameters of from 5 mm to 10 mm.In FIG. 1 an endoscopic clip applying apparatus is shown at 76. However,any elongated relatively narrow instrument is contemplated.

Referring once again to FIG. 3 in conjunction with FIG. 1, diaphragmmounting and stabilizing device 31 is formed of dual flanged circularribbed ring 32 having distally extending fingers 78 tapered at theirfree ends as shown. Diaphragm 30 is mounted to dual flanged circularring 32 as shown in FIG. 4 and the entire assembly is mounted to annularpartition 26 as shown. Fingers 78 are positioned within diaphragm innerwall 30a and are sufficiently flexible to conform to the shape of theinner wall while providing some degree of stability to the inner wall.Fingers 78 also assist in spreading inner wall 30a to expand aperture 34when an instrument is inserted by distributing the spreading force moreevenly. In addition to facilitating expansion of aperture 34 to conformto instrument 76, fingers 78 minimize the risk of damage to elastomericinner wall 30a, e.g., puncture thereof, by providing an interfacebetween the instrument 76 and the inner wall. Stabilizing device 31 isfabricated of a suitable flexible plastic material such as polyester,polypropylene, etc. and fingers 78 are preferably formed integral withdual flanged ring 32. Further, fingers 78 are sufficiently thin andflexible such that insertion into inner wall 30a of diaphragm 30 causesthem to assume an initial arcuate shape as shown in FIGS. 2 and 4,similar to the generally conical shape of inner wall 30a.

Upon insertion of instrument 76 into housing opening 20 and throughaperture 34 of inner wall 30a, the elastomeric material of wall 30a willexpand or stretch around the instrument 76 to form a fluid tight seal.The seal is of sufficient fluid tight character that media such aspressurized gases used to insufflate a body cavity or body liquids willnot pass the interface between diaphragm inner wall 30a and theinstrument 76. Aperture 34, in its non-expanded or non-stretchedcondition, is typically approximately 3 to 15 mm to accommodateelongated endoscopic instruments while maintaining sufficient sealedcontact with the other surface thereof. However, such dimensions willvary depending upon the size of the instruments and the intendedapplication. Further, manipulation of the instrument in any directionwill not affect the seal, since the elastomeric material will remain intight contact with the outer surface of the instrument.

At the point when the instrument 76 has passed the inner wall 30a andentered aperture 34, a gas tight seal has been created between theinstrument and the inner wall 30a. The surgeon then squeezes pins 60,62with the thumb and index finger causing the distal end of outer wall 30bof diaphragm 30 to expand to the shape shown in FIG. 1 thus permittingcontinued entry of the instrument 76 through the entire valve bodyhousing 15 and into the cannula 22. Depending upon the particularprocedure, the surgeon may prefer to squeeze pins 60,62 thereby openingouter wall 30b prior to entry of instrument 76 into the valve housing 15and into diaphragm inner wall 30a.

Cannula 22 is connected to the distal end of the valve housing at neck18 which has a series of alternating circular shaped ribs 80 and valleys82. Cannula 22 is fabricated of a rigid material such as a plastic,fiberglass or metal and is supported in position as shown in FIGS. 2 and4 within neck 18 by the ribs 80 which are formed of the same material.Alternatively, the tube 22 may be of elastomeric material in which caseit would simply be flexible and resilient so as to be assembled withdistal neck 18 by inserting the tube into the neck and distorting theouter shape until it is snapped into position as shown within ribs 80.

The operation of the valve assembly will now be described. The valveassembly is intended to be supplied as part of a cannula assembly, i.e.a valve assembly with distal cannula tube 22 positioned as shown. Atrocar is a sharp pointed instrument usually fitted within a cannulaassembly and used to insert the cannula into a body cavity by firstpiercing an aperture in the cavity wall (i.e., the peritoneum). Thecannula is then inserted into the punctured body wall of the patient.Thereafter, the trocar is removed, permitting insertion of instrumentsinto the patient's body through the cannula to perform the desiredprocedure. Thus, the significance of providing control to the surgeon ofthe sealed state of the opening in the cannula assembly cannot beover-emphasized. Such opening will ultimately control the exposurebetween the internal part of the body cavity and the outside atmosphere.For laparoscopic procedures the valve assembly will preserve the stateof insufflation of the peritoneum during the surgical procedures.

The surgeon removes the trocar from the cannula assembly therebypermitting the opening of outer wall 30b of diaphragm 30 to closeautomatically under the action of springs 48,50. Thereafter, the surgeoninserts an instrument into the body cavity by first inserting it intothe proximal end of the valve assembly, through dual flanged ring 32 andthen through aperture 34 of inner diaphragm wall 30a. Pins 60,62 may beselectively squeezed as desired by the surgeon to open the distal end ofouter wall 30b to permit entry of the instrument into cannula 22 andinto the body cavity. At this point, the tight contact between theinstrument 76 and the diaphragm inner wall 30a at aperture 34 has sealedthe inner body cavity from the outside atmosphere. This seal is providedby the resilient property of the stretched elastomeric materialsurrounding opening 34. Thus, separating clamp plates 40,42 to openouter diaphragm wall 30b to permit entry of instrument 76 into cannula22 does not affect the sealed condition of the inner anatomical cavity.As noted previously, manipulation of the instrument in any directionwill not affect the seal, since the elastomeric material defining theopening 34 will conform to the movements of the instrument and assume anelliptical or other shape necessary to maintain contact.

As noted, aperture 34 is preferably dimensioned between 3 and 15 mm toaccommodate laparoscopic and endoscopic instruments such as clipappliers, laser tubes, photographic instruments, tubes or the like.However, depending upon need or application this dimensional range maybe varied to accommodate any particular instrument.

The opening at the distal end of outer wall 30b is always under thesurgeon's control through pins 60,62 and is adapted to be automaticallyactuated to the closed duckbill shaped position 74 under action ofsprings 48,50 when the surgeon removes the instrument 76 or other objectfrom the valve assembly. Further, manipulation of the instrument 76 doesnot affect the shape of aperture 34 or the sealing contact of inner wall30 or with the instruments because diaphragm 30 is sufficiently flexibleand resilient to maintain contact with the surface of the instrument 76.Thus, during the entire sequence the integrity of the seal between theinside of the body cavity and the outside atmosphere is clearlymaintained at all times.

We claim:
 1. A trocar assembly having a channel defined along anelongate axis, the trocar assembly being adapted to receive aninstrument having a particular cross-sectional dimension, said trocarassembly comprising:an elastomeric septum disposed in said channel andincluding portions defining an orifice having in a relaxed state a firstcross-sectional area and in an expanded state a second cross-sectionalarea; and means responsive to the particular dimension of the instrumentfor expanding said orifice to the second cross-sectional area.
 2. Thetrocar assembly as recited in claim 1 wherein said first cross-sectionalarea is greater than zero.
 3. The trocar assembly as recited in claim 1wherein said second cross-sectional area is smaller than the particularcross-sectional area of said instrument.
 4. The trocar assembly asrecited in claim 1, and further comprising a seal housing adapted toreceive the elastomeric septum, the septum having seating portionspositioned radially outwardly of the orifice-defining portions andcontiguous therewith, said seating portions being attached to saidhousing for seating the septum therein,wherein the seating portions aredisposed in a first plane and said orifice-defining portions aredisposed in a second plane, said first and second planes being spacedalong said elongate axis.
 5. A valve assembly adapted to receive aninstrument having an outer surface and a cross-sectional dimension,comprising:a housing defining a channel extending therethrough along anelongate axis; a septum disposed in said housing and adapted to extendacross said channel, portions of the septum defining an orificecommunicating with the channel through the septum; at least saidportions of the septum being formed of an elastomeric material and beingexpandable radially outwardly to enlarge the orifice; and means pivotalon said housing and engaging the septum outwardly of the orifice forenlarging the orifice, said enlarging means being responsive to theinstrument for enlarging the orifice in proportion to thecross-sectional dimension of said instrument.
 6. A seal assembly adaptedto receive an elongate object and to form a seal around the object, theassembly comprising:a housing defining a channel configured to receivethe object moving generally axially through the channel; a septumextending across the channel of the housing and forming an outer sealwith the housing; portions of the septum defining a hole incommunication with the channel on both sides of the septum, the holehaving a size sufficient to receive the object with the hole portionsforming an inner seal with the object; the septum being formed of anelastomeric material having properties for producing a friction forcewhich resists movement of the object through the septum; and meansresponsive to insertion of the object into the channel for reducing thefriction force on the object.
 7. The assembly as recited in claim 6wherein the friction reducing means comprises:means responsive toinsertion of the object into the channel for measuring a particulardimension of the object; and means for stretching the septum inproportion to the particular dimension to enlarge the hole and therebyreduce the friction forces between the septum portions and the object.8. The assembly recited in claim 7 wherein the friction reducing meansfurther comprises:a frame; a plurality of levers each pivotal on theframe and engaging the septum to move the hole portions radially.
 9. Theassembly recited in claim 8 wherein the frame is annular and thefriction reducing means is disposed transverse to the channel in thehousing.
 10. A trocar assembly adapted to receive an instrument having aparticular cross-sectional dimension, said trocar assembly comprising:ahousing; an elastomeric member disposed within said housing and definingan orifice having in a relaxed state a first cross-sectional area and inan expanded state a second cross-sectional area; and means responsive tothe particular dimension of the instrument for expanding said orifice tothe second cross-sectional area.